10.2 error English Langauge Pack could not be found

just updated dopus to 10.2.0.0 and when I start dopus it says english langauge pack could not be found, and it won't start. I try to reinstall it again but the installer fails saying An error has occurred. Also the uninstaller does not appear in control panel programs now. Please help.

Error Code: -5001 : 0x80070002
Error Information:

SetupNew\setup.cpp (142)
PAPP:
PVENDOR:
PGUID:
$

Please try the last two items in the Problems installing Opus FAQ to see if either of them helps.

ok tried that, im on x64 so
first problem : windows explorer wont let me delete the InstallShield folder. Says I need permission from TrustedInstaller to make changes

I deleted the install ending in BF50D but it made no difference

Here's a guide which explains how to take permissions from TrustedInstaller:

helpdeskgeek.com/windows-7/windo ... installer/

Of course, do it on the InstallShield directory in question and not on the System32 directory that they use as an example.

Turns out installer had no digital signature and was corrupt. cleared stupid ie cache and redownloaded. thanks.